Enclosed load iron case switch HH12-32/3

型号：

HH12-32/3

电流：

32A

种类：

铁壳开关

The official name of the enclosed load iron shell switch/3 is an enclosed load switch or a fuse type load switch. It is a casing made of steel plate or cast iron, equipped with a fuse for cutting off short-circuit current, a knife switch for connecting and breaking the circuit, and an operating mechanism for operating the knife switch. It can therefore be manually operated for infrequent making and breaking of circuits and for short-circuit protection. The enclosed load iron case switch/3 is widely used in electrical installations in industrial and mining enterprises, electric lighting and rural power drainage and irrigation, and can be used for infrequent direct starting and stopping of small induction motors.
The fuse installed in the enclosed load iron case switch/3 has a relatively low ultimate breaking capacity (generally type R), so it should be installed at the end of the line where the short-circuit current is not large, otherwise it will act like an iron case. When a short circuit occurs in the line below the switch, the short-circuit current exceeds the breaking capacity of the fuse, and the fuse will explode, exacerbating the accident.
The knife switch of the enclosed load iron shell switch/3 is equipped with an energy-storage operating mechanism, which allows the knife to quickly open and close. An arc extinguishing cover is also installed on the contact, so the switching capacity is improved, and Because it is protected by an iron shell, it is not easy to cause an arc light injury accident during switching.
When the enclosed load iron case switch/3 is used to directly start and stop small induction motors infrequently, it is generally recommended to control motors below 0.00000000000000000000000000 yuan. Since most users use it to control motors below 0.000 liters, they have gained a lot of experience. When used to control motors above 0.0000000000000000000, there have been accidents of arc-burning hands. Because the iron shell switch contacts are not good enough, the fuse is easy to Therefore, the capacity of the motor started directly by the iron case switch should not be overused. From the comparison of technical and economic indicators, the iron case switch can only be used directly for motors below . Starting is more economical than turning off automatically.
In general electric heating and lighting circuits, iron-clad switches can be selected according to the rated current of the load. When used to control the full-voltage starting of a squirrel-cage asynchronous motor, the possibility of using an iron case switch to cut off the circuit when the motor is blocked must be taken into consideration, so the enclosed load iron case switch/3 must cut off the starting current of the motor, which is twice the rated current. . When controlling the motor, choose the iron case switch according to this principle. For example, the rated current of an electric motor is...